Competition law, known in the United States as antitrust law, is law that promotes or maintains market competition by regulating anti-competitive conduct by companies.
The history of competition law reaches back to the Roman Empire. The business practices of market traders, guilds and governments have always been subject to scrutiny, and sometimes severe sanctions. Since the 20th century, competition law has become global. The two largest and most influential systems of competition regulation are United States antitrust law and European Union competition law. National and regional competition authorities across the world have formed international support and enforcement networks.
Modern competition law has historically evolved on a country level to promote and maintain competition in markets principally within the territorial boundaries of nation-states. National competition law usually does not cover activity beyond territorial borders unless it has significant effects at nation-state level. Countries may allow for extraterritorial jurisdiction in competition cases based on so-called effects doctrine. The protection of international competition is governed by international competition agreements. In 1945, during the negotiations preceding the adoption of the General Agreement on Tariffs and Trade in 1947, limited international competition obligations were proposed within the Charter for an International Trade Organisation. These obligations were not included in GATT, but in 1994, with the conclusion of the Uruguay Round of GATT Multilateral Negotiations, the World Trade Organization was created. The Agreement Establishing the WTO included a range of limited provisions on various cross-border competition issues on a sector specific basis.